Superhigh-definition CMOS image sensor pixel circuit and control method thereof

Abstract

The invention discloses a superhigh-definition CMOS image sensor pixel circuit and a control method thereof. The circuit comprises a photosensitive element, a transmission pipe, a single-channel electron multiplier, a floating diffusion amplifier, a correlation double-sampling circuit, a row selection tube, a reset circuit and an analog-to-digital conversion circuit. The photosensitive element generates electrons, the transmission tube is closed, the correlation double-sampling circuit samples noise signals generated by the single-channel electron multiplier and the floating diffusion amplifier to obtain first sampling signals, and the row selection tube transmits the first sampling signals to the analog-to-digital conversion circuit; the transmission tube is opened, the floating diffusion amplifier converts the electrons after the multiplication of the single-channel electron multiplier into voltage signals, and the correlation double-sampling circuit samples the voltage signals to obtain second sampling signals; and the analog-to-digital conversion circuit performs correlation double-sampling processing according to the first sampling signals and the second sampling signals to obtain image signals. According to the invention, visible light with ultra-low illumination can be identified through low-solid-state noise.

Description

technical field [0001] The invention relates to the field of image sensing, in particular to an improvement of a pixel structure and a circuit of a CMOS image sensor for recognizing ultra-low illumination visible light and a circuit control method for ultra-high-definition requirements. Background technique [0002] In recent years, with the expansion of the scope and connotation of monitoring applications, especially the wide application of full HD and ultra-high It is difficult to monitor under low-illuminance conditions such as night monitoring of roads and residential areas, or even in ultra-low-illuminance environments such as underground roadways and tunnels. The production of the ultra-low illumination camera is a product produced to solve the application of this special ultra-low illumination environment. Its main advantage is that in an environment with very low illumination, it can increase the illumination as much as possible to capture the monitored object. . ...

AI Technical Summary

Problems solved by technology

Disadvantages: increase the size of the camera and increase the cost

Of course, when the automatic gain function (AGC) amplifies the signal, it also amplifies the noise, but the improvement in illumination is still very obvious

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